Electromechanical brake mechanism for motor vehicle

Abstract

The invention relates to an electromechanical brake device (1) for a motor vehicle, comprising a drive carrier (100) to which an electric motor (41, 42) and an actuating device (5) are attached, said actuating device being drivingly coupled to a motor shaft (411, 421) and by means of which a brake component can be adjusted, the motor (41, 42) has a motor housing (413, 423) in which a motor shaft (411, 421) extending in the axial direction is supported in and axially protrudes from an end bearing cover (414, 424), the motor housing (413, 423) being fixed to the driver carrier (100). In order to be able to improve production and assembly and maintain low installation space and weight, according to the invention, the drive carrier (100) has a recess (101) in which the motor housing (413, 423) can be received in an interlocking manner in the axial direction and in the radial direction, the motor housing (413, 423) can be supported on the end face against an axial bearing surface (104) of the recess (101).

Description

BACKGROUND

[0001] The invention relates to an electromechanical brake device for a motor vehicle, comprising a drive carrier to which an electric motor and an actuating device are attached, which is coupled in a geared manner to the motor shaft and by means of which the brake component can be adjusted, wherein the motor has a motor housing in which the motor shaft extending in the axial direction is mounted in a front-side bearing cover and axially projects therefrom, wherein the motor housing is fixed to the drive carrier.

[0002] Such a brake device of a motor vehicle is configured as a friction brake, wherein a brake component that is supported on the chassis and fixed relative to the rotation of the wheel to be braked can be brought into braking engagement with a counter-brake component that rotates with the wheel by means of the actuating device. During the braking engagement, a frictional contact is generated between the brake component and the counter-brake component, wherein the greater the brake torque generated by the friction, the higher the adjustment force applied in the adjustment direction by the actuating device.

[0003] A disc brake, which is known in principle and in which the counter-brake component is formed by a brake disc that rotates with the wheel and is axially accessible on both sides by brake calipers, is a widespread design. By means of at least one preferably linear actuation drive that is axially supported on the brake caliper, the brake component, usually brake pads, can be adjusted in the axial adjustment direction and thereby brought into frictional contact with the axial sides of the brake disc, wherein during the braking engagement the brake disc is frictionally clamped between the adjusted brake component and the other brake component that is axially supported on the brake caliper opposite to it.

[0004] It is known from DE 10 2017 123 266 A1 that the actuating device has two actuation drives arranged in series in the adjustment direction. Each of the actuation drives has a drive-side drive element and an output-side output element that is linearly adjustable in the axial adjustment direction relative to the drive-side drive element. In order to implement the adjustment movement, each drive element has a drive wheel, preferably a transmission wheel such as a gearwheel, which can be driven in a rotary manner about the axis of the drive wheel by an electric motor, an actuation motor. In each case, the rotation of the drive wheel is converted in the actuation drive into a relative adjustment movement or actuation stroke of the output element in the axial adjustment direction relative to the drive element. In the prior art discussed, the two drive wheels of the first and second actuation drives are arranged coaxially on a common axis in the axial adjustment direction.

[0005] In each case, the actuating drive forms a lifting device or adjustment device which is effective axially in the adjustment direction. For example, the actuating drive can have a spindle drive, wherein the drive element has a spindle nut and the output element has a threaded spindle engaged in the spindle nut, or the output element has a spindle nut and the drive element has a threaded spindle engaged in the spindle nut. Other designs of the actuating drive can also be used, which can include, for example, ramp bearings, cam disks, ramp pin arrangements, etc., and likewise convert a rotation of the drive element into a linear adjustment of the output element.

[0006] The actuating device and the motor are mounted on a drive carrier, such that a transmission wheel, for example a gear wheel, mounted on a rotatably driven motor shaft of the motor engages with a drive wheel gear of the actuating drive, as described in the above-mentioned document DE 10 2017 123 266 A1. The drive carrier is connected to the brake caliper. The drive carrier has a plate-like mounting portion which extends flat, and the motor is fixed on this plate-like mounting portion, such that the motor shaft and an axis of the actuating device which is parallel to the motor shaft are perpendicular with respect to the drive carrier.

[0007] The motor has a motor housing in which the motor shaft including the rotor is mounted in a rotatable manner, and which is connected to the drive carrier. The motor housing comprises a front-side bearing cover through which the motor shaft is axially guided to the front toward the drive carrier. The bearing cover is connected to the motor housing which is connected to the drive carrier.

[0008] For smooth and low-wear operation, the motor shaft must be oriented parallel at a defined spacing from the axis of the actuating drive, in order to ensure optimum gear engagement. This requires the motor to be precisely positioned with respect to the actuating drive on the drive carrier and to be firmly fixed on the drive carrier. The effort involved in production and assembly, as well as the required installation space and weight, should be as low as possible. However, a disadvantage of the known embodiments is that the assembly and alignment of the motor housing on the drive carrier is complex.

[0009] In view of the above-mentioned problems, it is an object of the present application to be able to improve production and assembly, and to keep the installation space small and the weight low. SUMMARY

[0010] According to the application, the object is achieved by a brake device having the features of claim 1. Advantageous refinements emerge from the dependent claims.

[0011] In the case of an electromechanical brake device for a motor vehicle, the brake device comprises a drive carrier to which an electric motor and an actuating device are attached, which is coupled in a gear- driven manner to the motor shaft and by which the brake component can be adjusted, wherein the motor has a motor housing in which the motor shaft extending in the axial direction is mounted in a front-side bearing cover and axially projects therefrom, wherein the motor housing is fixed to the drive carrier, it being provided according to the invention that the drive carrier has a recess in which the motor housing can be received in a form-locked manner in the axial and radial directions, wherein the motor housing can be supported on the front-side portion against an axial bearing surface of the recess.

[0012] The recess provides a receiving portion for the motor, in which the motor housing can be received in a defined manner, such that the motor housing is oriented in an axially and radially defined manner relative to the drive carrier. The recess has an opening through the drive carrier, and the motor shaft is guided perpendicularly through this opening by the drive carrier.

[0013] The bearing surface can be formed on a bearing protrusion projecting radially inward into the opening of the recess, for example on a step or the like arranged at the edge of the opening. The opening cross section of the recess is adapted to the outer cross section of the motor housing, such that the motor housing can be introduced in the axial direction, defined as in the direction of the motor axis defined by the motor shaft, toward the front, with a small radial play, into the recess until the motor housing comes into axial contact with the bearing surface. Here, the motor shaft projects on the side of the drive carrier facing away from the motor.

[0014] The bearing cover arranged on the front end side of the motor housing can be supported against the bearing surface and supported with the motor housing.

[0015] One advantage is that the motor housing is supported in the radial direction in a form-locked manner when inserted into the recess and also in the axial direction in a form-locked manner when it comes into contact with the bearing surface. Thus, the motor received in the recess is positioned in a spatially defined manner relative to the drive carrier. The support for fixing the motor can be carried out after insertion into the recess. Thus, assembly is advantageously simplified, and a defined gear engagement with the actuating device can be provided simply, for example via a drive wheel of the motor shaft and a drive wheel of the actuator that engage into one another.

[0016] The bearing surface can be formed on a radially inwardly projecting protrusion in the recess. The protrusion can preferably have a peripheral step or the like that extends around the interior of the recess at least on a portion of the periphery, and the bearing surface is formed on this peripheral step parallel to the flat extent of the mounting portion of the drive carrier.

[0017] It is preferred that the bearing cover is attached to the motor housing on the front side. The bearing cover can here initially be provided as a separate component and can be assembled with the motor housing after the rotor and the motor shaft are inserted. This enables the motor to be installed in an efficient manner.

[0018] It can be provided that the bearing cover is axially supported against the support surface. The bearing cover, which is axially attached to the motor housing at the front, can be positioned with its front end side, which faces away from the motor housing, against the support surface. The bearing cover is connected to the motor housing on its rear side, which axially faces away from the front side.

[0019] It is advantageous if the bearing cover can be supported between the support surface and the motor housing. Here, the bearing cover has at least one portion which is arranged axially between the motor housing and the support surface. Thus, the bearing cover can be supported axially against the motor housing by virtue of the fact that it is supported against the support surface. In other words, the bearing cover is at least partially in the force flow of the support of the motor housing to the drive carrier. This allows the motor to be fixed to the drive carrier and the bearing cover to be fixed to the motor housing during the support in a single assembly step, so that work is advantageously reduced.

[0020] For example, the bearing cover can have an axial shoulder which is inserted into an axial opening of the motor housing and a peripheral collar which protrudes radially outwards in the cross section of the opening. The collar can have substantially the same outer cross section as the motor housing and is arranged axially between the support surface and the motor housing. This allows the bearing cover to be supported on the support surface and fixed to the motor housing at the same time when the motor housing is supported against the support surface. One advantage here is that the bearing cover only needs to be temporarily connected to the motor housing before the motor is installed in the brake device and the final fixing can be carried out in one assembly step when the motor is supported to the drive carrier. Thus, the support achieves a dual function of fixing the motor to the drive carrier and fixing the bearing cover to the motor housing. For example, the bearing cover can be inserted into the motor housing only in a non-positive manner by means of the axial shoulder or can be inserted onto the motor housing. This eliminates the need for expensive screw, weld or other joining connections between the bearing cover and the motor housing, thus simplifying the construction of the motor and can save weight.

[0021] It can be preferably provided that the motor housing has a flange element which is axially spaced apart from the end side and protrudes radially beyond the recess.

[0022] The flange element protrudes radially outward from the motor housing and beyond the recess. The flange element can be connected to the driver carrier. For this purpose, fastening means can be provided which can be connected to the driver carrier outside the recess in order to support the motor housing axially against the outer side of the brake housing. For example, a plurality of axial flange holes can be provided in the flange element distributed over the circumference, through which fastening elements such as screws can be guided and can be screwed into corresponding threaded holes in the driver carrier. Since the flange element is axially spaced from the front end side of the bearing cover, the motor housing which protrudes into the recess can be supported by the flange element against the driver carrier with the bearing cover on the front side against the bearing surface arranged in the recess. In this way, the motor can be fixed in the position defined by the recess on the driver carrier by the flange element, and at the same time, the bearing cover can thus be supported and firmly connected to the motor housing.

[0023] The axial distance of the flange element from the front side of the bearing cover mounted on the front side at the front of the motor housing is preferably greater than the depth of the recess measured from the bearing surface to the outer side of the driver carrier in the area of the flange element. This allows the bearing cover to be axially clamped between the bearing surface and the motor housing by supporting the flange element. The advantage is that by connecting the motor housing to the driver housing, the bearing cover can be firmly connected to the motor housing without additional connecting means. This allows the motor to have a simpler and lighter design.

[0024] It can be provided that the motor housing has at least partially a hollow cross section on which the bearing cover can be fixed in a form-locked manner. The motor housing can for example have a pot or cup shape design and can be axially closed at the front by the bearing cover attached to the motor housing. The motor shaft with the rotor can be mounted on the inner side of the motor housing in the end region and can with its other end region be mounted in a rotatable manner in the bearing cover and guided through the bearing cover to the outside. The hollow cross section can for example have a substantially cylindrical tubular portion on the open end side of which the bearing cover can be fixed by axial support. For example, a cylindrical extension of the bearing cover can be inserted in a form-locked manner into the opening of the hollow cross section and a substantially annular collar can be clamped in the manner described above between the bearing surface and the end side of the tubular portion.

[0025] Advantageously, the motor housing, the bearing cover and / or the driver carrier comprise a casted component. The casted component can be an injection molded piece made of a thermoplastic material which can optionally be fiber reinforced for increased strength or can be a die cast piece made of a metallic material such as an aluminum, magnesium or zinc alloy. Using a casting method, complex shapes can be effectively realized. For example, the recess and possibly other functional elements according to the application can be molded in one piece on the driver carrier. Correspondingly, the flange element and possibly other functional elements can be molded in one piece on the motor housing. For example, an extension for connecting to the motor housing, a bearing seat for a motor shaft, etc. can be molded in one piece on the bearing cover.

[0026] Between the recess and the motor housing, an elastically deformable O-ring made of rubber or a polymer material can be arranged which is radially clamped between the circumferential inner surface of the recess and the outer surface of the motor housing. Thus, by simply inserting the motor housing into the recess in the axial direction, the motor housing can be held in place on the driver carrier in a non-positive or frictional manner, whereby a subsequent support can be simplified. It can be advantageous to provide that the O-ring is received in a groove extending on the circumference of the recess or the motor housing and is thus held in a positively locking manner in the axial direction.

[0027] In addition, the O-ring or another elastic sealing element can effectively seal the motor housing in the recess against the ingress of moisture or contaminants.

[0028] Preferably, it can be provided that the driver carrier has at least two recesses. In each of the recesses, a motor can be fixed, each of the motors can drive an actuation drive of an actuation device. This makes it possible to install two motors to drive two actuation drives of actuation devices on the driver carrier. Advantageously according to the application, the two motors can be easily and safely positioned and installed relative to the actuation drives.

[0029] One advantageous embodiment can provide that the brake device comprises an actuation device and a brake component connected to the actuation device, which brake component can be adjusted by the actuation device along the axis and can be braked into engagement with a counter-brake component, wherein the actuation device has a first actuation drive and a second actuation drive coupled in series to the first actuation drive, wherein the first actuation drive has a rotatably driven first drive wheel and the second actuation drive has a rotatably driven second drive wheel which is coaxial to the first drive wheel, wherein a clutch device is arranged between the first drive wheel and the second drive wheel.

[0030] The actuating device can be driven by at least one electric actuating motor. The at least one electric actuating motor is preferably geared to at least one drive wheel. Preferably, one actuating motor can be provided for each of the first and second drive wheels. According to the present invention, one or more actuating motors can be activated by a wheel brake control unit assigned to the braking device.

[0031] It can be provided that the clutch device is designed as a friction clutch having a friction element which, during engagement of the clutch, can be connected in a frictionally locking manner to a counter-friction element.

[0032] Hereinafter, the first drive wheel and the second drive wheel are also referred to together as two drive wheels or simply as drive wheels.

[0033] The drive wheels can each be designed as a gear, for example a spur gear, or as a pulley or a toothed belt pulley or a worm gear, so that generally a transmission wheel is provided, via which the drive torque from the electric actuating motor can be coupled into the actuating drive.

[0034] A friction clutch is provided between the drive wheels. The friction clutch comprises a friction element connected to one of the drive wheels in a torque-locking manner, and a corresponding counter-friction element connected to the other drive wheel in a torque-locking manner. The friction element and the counter-friction element can achieve a frictionally locked coupling at any relative angular position. Unlike a form-locking latching connection, a purely non-positive clutch is achieved here. Therefore, compared to the discrete latching steps of a latching connection, the relative position of the drive wheels relative to each other can be continuously predefined. This allows for uniform and continuous adjustment of the second actuator relative to the first actuator, and the air gap can be continuously adjusted. This is particularly advantageous for evenly tracking the optimal operating point of the braking device and the ongoing wear of the brake components, i.e., the ongoing wear of the brake pads, during operation. Compared to options with only stepped adjustment, this allows for a continuously improved response behavior of the braking device, resulting in increased operational reliability and greater operating comfort.

[0035] Another advantage over a latching clutch is that, to actuate and release the clutch device, essentially no axial relative movement is required between the clutch elements in the engaged clutch state, for example, between the drive wheels or the latching elements. These elements must inevitably be movable relative to one another in order to produce and release a latchable, form-locking connection. In contrast, according to the present invention, the purely non-form-locking connection between the friction element and the counter-friction element can be simply predetermined by the applied axial actuation force, without the friction element and the counter-friction element having to move axially relative to one another. This results in a simpler and more reliable design of the clutch device.

[0036] It is preferably provided that the friction clutch has a clutch torque which can be specified in a defined manner. The clutch torque indicates a maximum differential torque which can be transmitted in a non-positive manner between the friction element and the counter-friction element by a frictional locking connection in the clutch engagement. When this clutch torque is exceeded, the clutch device slips, so that the two drive wheels rotate relative to one another. One advantage here is that the friction clutch according to the application continuously slips, so that an improved, uniform readjustment of the air gap can be achieved. Furthermore, it is not necessary to structurally consider and absorb an axial offset movement of the latching elements as in the case of known latching clutches.

[0037] It is advantageous if the friction element and the counter-friction element are arranged coaxially. This coaxial arrangement here corresponds to a coaxial arrangement of the drive wheels. The friction element and the counter-friction element can be arranged in the region of those end sides of the drive wheels which are directed opposite one another in the axial direction in a structurally simple manner and with a compact overall design. Due to the purely non-positive connection resulting from the clutch as described above, no movable parts are required.

[0038] In an advantageous embodiment, it can be provided that the friction element and the counter-friction element have a conical design. The friction element can have a conical portion which converges at least partially in the axial adjustment direction and has a conical friction surface, which can be designed as an outer or inner cone, and a corresponding conical portion on the counter-friction element, which is correspondingly designed as an inner or outer cone in the opposite direction and has a conical counter-friction surface. In order to produce the engagement of the clutch, the outer cone enters the inner cone, wherein the conical friction surface and the conical counter-friction surface are loaded against one another in a friction-locked manner by an axial actuation force of the clutch. One advantage here is that the axially acting actuation force of the clutch can be converted into a normal force acting between the conical friction surfaces during the frictional contact by the conical portions. Thus, a relatively small axial actuation force of the clutch can be converted into a larger normal force in the frictional contact by a relatively small inclination, whereby a high clutch torque has already been achieved by a relatively small axial actuation force of the clutch.

[0039] As an alternative to or in addition to the above-described embodiment, it can be provided that the friction element and the counter-friction element have a planar design. In a manner similar to a disc clutch, the mutually corresponding friction surfaces are here designed at least partially as flat axial surfaces. In particular in the case of only a relatively small clutch torque being achieved, a space-saving arrangement can be achieved.

[0040] It can be preferred that the friction element and the counter friction element are preloaded against each other. Preferably, the friction element and the counter friction element are preloaded elastically or spring- elastically against each other. The friction surface and the counter friction surface are pressed against each other in a frictionally locked connection by a predetermined axial preloading force. In order to generate the preloading force, an elastic preloading element, for example a spring element or the like, can preferably be provided. The clutch torque of the friction clutch is determined by an actuating force acting perpendicularly with respect to the friction contact, i.e. a force applied axially between the friction element and the counter friction element, wherein a greater preloading force results in a greater clutch torque. This offers the advantageous possibility of simply predetermining the clutch torque by the preloading force applied by the preloading element. For example, in the case of a spring element which is flexible in the axial direction under pressure, such as a compression spring, the preloading force applied can be simply predetermined and adjusted by the spring constant and the compression of the spring.

[0041] The above-described embodiments can advantageously be implemented in such a way that the friction element and / or the counter friction element is axially displaceable and is supported against the first drive wheel or the second drive wheel via an axially acting spring element. The friction element or the counter friction element is connected to one drive wheel in a torque-locked and axially displaceable manner, for example via a radially protruding driver, which produces a non-positive connection effective in the circumferential direction. The spring element, which is axially clamped between the friction element or the counter friction element and one drive wheel and is preferably designed as an axially acting compression spring, ensures that the friction element or the counter friction element is axially preloaded against the corresponding counter friction element or friction element, which is axially supported on the other drive wheel, i.e. axially pressed against the other drive wheel during the frictional contact. The corresponding counter friction element or friction element is fixedly connected to the respective other drive wheel for co-rotation. Alternatively or additionally, the counter friction element can also be supported on one of the drive wheels via a spring element. One advantage of this arrangement is that such a friction clutch can be incorporated between the drive wheels in a structurally simple and space-saving manner.

[0042] In an advantageous refinement, the friction element and / or the counter friction element can be arranged in the first drive wheel or the second drive wheel. For example, one drive wheel can be designed in a substantially drum shape, and the friction element or the counter friction element can thus be arranged in an inner space enclosed by a rotating gear or gear rim. This allows a compact design which is protected from external influences. Thus, for example, the drive wheel of the first actuating driver can have a conical friction element which engages axially in a counter friction element designed as an inner cone and arranged at least partially within the second drive wheel.

[0043] A particularly compact design can be achieved, in particular in the last-mentioned embodiment, since the drive wheel is arranged within the axial extent of the actuating drive, i.e. the drive wheel is not attached axially protruding on one side.

[0044] It is preferred that the friction element and / or the counter friction element have a friction lining. The friction element and the counter friction element preferably have a metal body, which is made of steel, for example. In order to avoid metal-to-metal contact, a coating or a lining for creating a friction pair with a defined friction force can be applied, which is made of sintered material, metallic and / or ceramic friction material, composite material, etc., for example. This can ensure a defined, reproducible clutch torque.

[0045] It can be provided that the actuating drive has a spindle drive. In this case, in a manner known per se, a threaded spindle engages into a spindle nut and is driven in relative rotation via a drive wheel connected to the threaded spindle or the spindle nut. The spindle nut can form a drive-side drive element of the actuating drive, and the threaded spindle can form an output-side output element, which can be linearly adjusted relative to the drive-side drive element, or the spindle nut can form an output-side output element, and the threaded spindle can form a drive-side drive element of the actuating drive.

[0046] The actuating drive can have a ball ramp arrangement, a wedge disc arrangement or a ramp pin arrangement. In the case of a ball ramp arrangement, also referred to as a ramp bearing, the drive element and the output element preferably have cam discs, which have raceways or ramps, which are inclined relative to the axis and between which balls are arranged, which can roll in the circumferential direction. As a result of the balls rolling on the ramps, a relative rotation results in the output element being axially displaced relative to the drive element. In a ramp pin arrangement known per se, a ramp pin is arranged between the drive element and the output element and is each supported in the circumferential direction such that, in the case of a relative rotation, the ramp pin is inclined more or less relative to the axis depending on the direction of rotation, whereby the distance between the drive element and the output element is also adjustable.

[0047] In the actuating device, two identically acting actuating drives can be combined with one another as first and second actuating drives, for example two spindle drives. It is also possible to combine two different designs, for example a ball ramp arrangement as first actuating drive and a spindle drive as second actuating drive, for adjusting the air gap. The respective characteristic properties of each design can be optimally utilized. For example, a non-linear adjustment characteristic and / or at least partial self-locking properties and / or defined dead points or extended positions allowing a defined adjustment path can be realized with a ball ramp arrangement with little complexity. The implementation of the aforementioned form-fit properties can at least partially require an exact specification of the air gap, which can be realized without any problems using the friction clutch according to the application.

[0048] The brake device according to the application can comprise an actuating device and a brake component connected to the actuating device, which can be adjusted by the actuating device along an axis and can be brakedly engaged with a counter brake component, wherein the actuating device has a first actuating drive and a second actuating drive coupled in series to the first actuating drive, wherein the first actuating drive has a first drive wheel that can be driven in rotation and the second actuating drive has a second drive wheel that can be driven in rotation, which is coaxial to the first drive wheel, wherein a clutch device is arranged between the first drive wheel and the second drive wheel.

[0049] The actuating device can be driven by at least one electric actuating motor. The at least one electric actuating motor is preferably in toothed engagement with at least one drive wheel. Preferably, one actuating motor can be provided for each of the first drive wheel and the second drive wheel. According to the application, the actuating motor or motors can be activated by a wheel brake control unit assigned to the brake device.

[0050] In the last-mentioned embodiment of the brake device, it can be provided that the clutch device is configured as a friction clutch having a friction element, which can be connected to a counter friction element in a frictionally engaging manner during engagement of the clutch.

[0051] This makes it possible to realize the advantages explained above in connection with the brake system.

[0052] To implement the method according to the application, it can be provided that the brake device has an actuation device, which can be coupled to the actuation motor and comprises a first actuation drive and a second actuation drive coupled in series to the first actuation drive, and which acts on the brake component, which can be braked in the direction of the axis with the counter-brake component, wherein the first actuation drive has a first drive wheel, which can be driven in rotation, to which a first drive torque can be applied for actuation, and the second actuation drive has a second drive wheel, which can be driven in rotation, which is coaxial to the first drive wheel and to which a second drive torque can be applied for actuation, wherein a clutch device is arranged between the first drive wheel and the second drive wheel, wherein according to the application it is provided that the clutch device is configured as a friction clutch and has a predefinable clutch torque, which, when exceeded, causes the first drive wheel to slip relative to the second drive wheel, wherein, for actuation of the first actuation drive, the first drive wheel and the second drive wheel are driven synchronously, so that the second actuation drive remains unactuated, and, for actuation of the second actuation drive, the second drive wheel is driven and the first drive wheel is stopped relative to the second drive wheel, so that the friction clutch slips and the first actuation drive remains unactuated.

[0053] The above-described features in connection with the brake device according to the application can be used individually and in combination for implementing the method according to the application.

[0054] To adjust the first actuation drive, an actuation torque can be coupled into the first drive wheel by means of a first electric actuation motor, and correspondingly, the second actuation drive can be driven by a second electric actuation motor.

[0055] During normal braking mode, the first drive wheel and the second drive wheel rotate synchronously. First, this can be achieved by the first drive wheel and the second drive wheel being driven by the first actuation motor and the second actuation motor with synchronous drive torques. Second, during the drive of the first drive wheel, the second drive wheel can be brought along synchronously by the clutch device as long as the transmitted drive torque remains below the clutch torque. In this operating mode, the second actuation drive remains unactuated and idles as a whole with the brake element.

[0056] In this method, when the clutch torque is exceeded, in order to adjust the air gap, the clutch device can be continuously and uniformly slipped. This can be achieved, for example, by stopping the drive wheel of the first actuating drive, for example by corresponding actuation of the brake or the first drive motor, while a second drive torque greater than the clutch torque is applied to the second drive wheel by the second drive motor. The second drive wheel thus rotates relative to the first drive wheel, and by actuating the second actuating drive, the air gap can be continuously and finely adjusted, so that continuous progressive wear on the brake elements or brake pads can be optimally compensated.

[0057] The first drive wheel and the second drive wheel can be coupled in a torque-transmitting manner by means of a friction clutch in order to produce synchronous driving.

[0058] In this case, it is not necessary for the two drive wheels to be driven synchronously by the actuating motor. Any torque differences can be compensated within a predetermined tolerance range.

[0059] It can be advantageous to provide that a higher clutch torque is specified when the first actuating drive is actuated than when the second actuating drive is actuated. The first actuating drive is actuated by synchronous driving of the first drive wheel and the second drive wheel. The friction element and the counter-friction element are preloaded against one another by means of the spring force of the spring element, and in addition, the adjustment force of the first actuating drive acts counter to the spring force. This results in a relatively high clutch torque. By contrast, if only the second drive wheel is rotated in order to adjust the air gap, only the spring force comes into play, so that a lower clutch torque is set. This facilitates adjustment of the air gap. BRIEF DESCRIPTION OF DRAWINGS

[0060] Advantageous embodiments of the application will be described in more detail hereinafter with reference to the accompanying drawings, in which:

[0061] Figure 1 a schematic perspective view of a brake device according to the application is shown,

[0062] Figure 2 a side view of a brake device according to Figure 1 is shown,

[0063] Figure 3 a schematic perspective view of an actuating device according to the application of a brake device according to Figure 1 is shown,

[0064] Figure 4 a section through a brake device according to Figure 1 is shown,

[0065] Figure 5 a schematic perspective view of a brake device according to Figure 1exposed schematic perspective view of a first actuating drive of the brake device,

[0066] Figure 6 an enlarged detail view of the actuating device according to Figure 4 is shown, and

[0067] Figure 7 a longitudinal section through a motor mounted on a drive carrier of the brake device is shown. DETAILED DESCRIPTION

[0068] In the various figures, identical components are always provided with identical reference numerals and will generally therefore also only be named or referred to in each case once.

[0069] Figure 1 A brake device in the form of a disc brake as a whole is shown according to the application. The brake device comprises a brake disc 2 which forms a counter-braking component and which is connected to a vehicle wheel which can be rotated about a wheel axis R and which is not shown here. A brake caliper 3 reaches around both axial end faces of the brake disc 2.

[0070] The brake disc 2 is designed here as a non-ventilated brake disc made of solid material. As an alternative, the brake disc 2 can also be designed as an internally ventilated brake disc.

[0071] An electric brake actuator 4 according to the application is attached to the brake caliper 3, which electric brake actuator 4 is shown in Figure 3 in a separate, exposed schematic perspective view and is explained in detail in Figures 4 to 6 .

[0072] The brake actuator 4 comprises an actuating device 5 which extends axially in the direction of an axis A which is positioned parallel to the wheel axis R and which indicates an adjustment direction V of the actuating device 5.

[0073] As can be seen in the sectional view along the axis A in Figure 4 , the brake disc 2 is arranged axially between two brake pads 31 and 32. One brake pad 31 is fixedly borne on the brake caliper 3 on the side facing away from the brake actuator 4. The other brake pad 32 which forms a braking component within the meaning of the application is attached to the actuating device 5 and can be adjusted by the actuating device 5 in an axial adjustment direction V indicated by the axis A towards the brake disc 2 in order to produce a braking engagement, as is indicated by the arrow in Figure 4 .

[0074] In the unactuated state of the brake device 1, an axial air gap L is located between the brake disc 2 and the adjustable brake pad 32, which is shown schematically in Figure 4 in an enlarged width.

[0075] The configuration of the actuation device 5 is illustrated in Figure 4 and in Figure 6 in its enlarged detail.

[0076] The actuation device 5 comprises a first actuation drive 6 having a ball ramp arrangement, also referred to as a ramp bearing, and a second actuation drive 7 which is coupled in series to the first actuation drive 6 in the axial direction (relative to the axis A) and has a spindle drive.

[0077] The first actuation drive 6, which is formed in the illustrated example as a ball ramp arrangement or ramp bearing, comprises a drive-side cam disk 61 which is fixedly supported on the brake actuator 4 for rotation therewith in the axial direction, and an output-side cam disk 62. Between the cam disks 61 and 62, balls 63 are arranged. As can be seen in the schematic exposed view in Figure 5 , the cam disks 61 and 62 have mutually axially opposite ramp-like raceways 64 which are positioned obliquely relative to the axis A, and the balls 63 can roll between the raceways 64. In the above- Figure 5 , a rotation of the output-side cam disk 62 relative to the fixed drive-side cam disk 61, as is schematically indicated by the curved arrow, results in a linear adjustment of the output-side cam disk 62 in an adjustment direction V which is parallel to the axis A. Thus, as is illustrated in Figure 4 , the brake pad 32 can be brought into braking engagement by actuating the first actuation drive 6.

[0078] The cam disk 62 is connected to a coaxial gear wheel 65 which is in the form of a spur gear and forms a drive wheel in the context of the invention.

[0079] The gear wheel 65 is in gear engagement with a first electric actuation motor 41, also referred to simply as motor 41. This achieves a rotary drive of the cam disk 62 and thus an actuation of the first actuation drive 6.

[0080] The second actuation drive 7, which is in the form of a spindle drive in the illustrated example, has a threaded spindle 71 on the output side which engages in an internal thread of a drive-side spindle nut 72. The internal thread is formed in the output-side cam disk 62 of the first actuation drive 6, so that the functional combination of the output-side cam disk 62 and the drive-side spindle nut 72 is in one component.

[0081] The threaded spindle 71 is connected via a hub part 74 to a coaxial gear wheel 75, which is rotatably mounted in an axially fixed manner in the brake actuator 4. The threaded spindle is coupled in a torque-locked but axially displaceable manner via a driver 73 to the gear wheel 75, which can have, for example, radially protruding lugs or teeth that engage in an axially movable manner in an axial groove of the hub part 74.

[0082] Like the gear wheel 65, the gear wheel 75 can be designed as a spur gear and arranged coaxially adjacent to the gear wheel 65. This gear wheel 75 is in gear engagement with the second electric actuation motor 42, also referred to as motor 42. This achieves a rotational drive of the threaded spindle 71 and thus an actuation of the second actuation drive 7.

[0083] The threaded spindle 71 is connected axially via a thrust bearing 43, for example an axial rolling bearing as shown, to a thrust member 44, to which the displaceable brake pad 32 is attached, as can be seen in Figure 4 The thrust member 44 can also be referred to as a piston.

[0084] The clutch device has a friction element 8, which is guided as a coaxial conical shoulder from the cam disc 62 towards the second actuation drive 7. The conical shoulder has a conical friction surface 81 arranged on the outer side of the outer cone. The friction element 81 can preferably be formed integrally with the cam disc 62 / spindle nut 72.

[0085] When the clutch is engaged, the friction element 8 is coupled in a friction-locked manner to a counter friction element 9. Here, the conical shoulder axially enters a corresponding conical opening in the counter friction element 9, which has a conical friction surface 91 arranged in the inner cone. When the clutch is engaged, the friction surface 81 and the counter friction surface 91 are positioned in frictional abutment with one another in a friction-locked manner, as can be clearly seen in Figure 6 .

[0086] The counter friction element 9 is coupled in a torque-locked but axially displaceable manner via a driver 92 to the gear wheel 75, which engages in a corresponding groove 76 in the hub part 74 or the gear wheel 75.

[0087] A spring element 93 is provided between the gear wheel 75 or the hub part 74 connected thereto and the counter friction element 9. Due to the axially acting spring force of the spring element 93, the counter friction element 9 is resiliently pressed against the friction element 8. As a result, a defined clutch torque of the friction clutch according to the application is produced by the friction element 8 and the counter friction element 9.

[0088] Figure 3It is shown how the two motors 41, 42 and the actuating device 5 are arranged relative to the brake caliper 3. For the sake of an improved overview, the driver carrier 100 is omitted in this figure.

[0089] Each of the motors 41, 42 has a motor shaft 411, 421 which can be driven in a rotational manner about a motor axis M and is positioned parallel to the axis A. A gearwheel 412 or 422 is mounted on each of the motor shafts 411, 421, which in each case engages with a gearwheel 65 or 75 of the actuating device 5.

[0090] Each motor 41, 42 has a motor housing 413, 423 which in the example shown has a cylindrical basic shape. The motor housing has a cup-shaped shape design and in each case the motor housing is axially closed at its observer-facing axial end side in Figure 3 the bearing cap 414, 424, wherein the motor shaft 411, 412 supporting the rotor of the motor 41 is in each case mounted in the bearing cap 414, 424 and axially protrudes from the bearing cap 414, 424.

[0091] Figure 7 A longitudinal section through the motors 41 and 42 along the motor axis M is shown, wherein for the sake of improved clarity only the reference numerals for the motor 41 have been added, however, these reference numerals are also present in the other motor 42, respectively.

[0092] The driver carrier 100 has a recess 101 which comprises an opening 102 through the driver carrier 100. A protrusion 103 projecting radially inwards into the opening cross section in a stepped manner has an axial bearing surface 104 which is guided against the motor 41. The recess 101 is radially outwardly delimited by an inner surface 105 which extends coaxially relative to the motor axis M.

[0093] The inner surface 105 is adapted to the outer diameter of the motor housing 413, such that the motor housing 413 can be axially inserted into the inner surface 105 and is held and supported radially, i.e. transversely relative to the motor axis M, in a form-fittingly locked manner.

[0094] The bearing cap 414 is axially inserted into the motor housing 413 with an axial shoulder 415 from the front. The bearing cap 414 is positioned with its front end side, which according to definition points to the front and in Figure 7 the figure to the left, axially against the bearing surface 104 of the recess 101.

[0095] Furthermore, the bearing cap 414 has a circumferential, radially protruding collar 416, which is arranged axially between the motor housing 413 and the bearing surface 104.

[0096] The motor housing 413 has a flange element 416, which protrudes radially outwards beyond the recess 101 with an axially continuous flange hole, through which a screw 417 as a fastening element is guided and screwed into a corresponding threaded opening in the driver carrier 100.

[0097] By screwing in and tightening the screw 417, the motor housing 413 is fixed to the driver carrier 100 and is supported with the driver carrier 100. Here, the bearing cap 414, together with the motor housing 413, is supported axially against the bearing surface 104 (in the direction of the arrow to the left) and at the same time is pressed axially into the motor housing 413 (in the direction to the right) and is fixed. The screw 417 thus has a dual function for fixing the motor 41 to the driver carrier 100 and for connecting the bearing cap 414 to the motor housing 413. Here, the bearing surface 104 and the inner surface 105 provide a defined orientation of the motor 41 relative to the driver carrier 100. Figure 7 Figure 7

[0098] Furthermore, an O-ring 106 made of an elastic elastomer or rubber material can be arranged between the motor housing 413 and the inner surface 105, for example as shown, in a groove extending around the inner side of the inner surface 105. The O-ring is elastically clamped there in the radial direction and ensures that the motor housing 413 is held in the recess 101 in a friction-locked manner by simple axial insertion - in the direction of the arrow to the left. Figure 7 In addition, the motor 41 can be sealed in this way relative to the driver carrier 100.

[0099] The bearing cap 414 has a receiving opening 418, through which the motor shaft 411 extends, wherein, opposite the bearing cap 414 between the motor shaft 411 and the receiving opening 418, a bearing 419 for the rotatable mounting of the motor shaft 411 is arranged, which is designed as an antifriction bearing, more precisely as a radial groove ball bearing. The receiving opening 418 has an inwardly protruding shoulder portion 418a, against which the bearing 419 is positioned in the direction of the motor axis M and on which the bearing 419 is supported.

[0100] List of reference signs

[0101] 1 brake device

[0102] 100 driver carrier

[0103] ​​101 recess

[0104] 102 opening

[0105] 103 protrusion

[0106] 104 support surface

[0107] 105 inner surface

[0108] 106 o-ring

[0109] 2 brake disc

[0110] 3 caliper

[0111] 31, 32 brake pad

[0112] 33 fastening bolt

[0113] 4 brake actuator

[0114] 41, 42 motor (actuation motor)

[0115] 411, 421 motor shaft

[0116] 412, 422 gearwheel

[0117] 413, 423 motor housing

[0118] 414, 424 bearing cap

[0119] 415, 425 shoulder

[0120] 416, 426 flange element

[0121] 417, 427 screw

[0122] 418 receiving opening

[0123] 418a shoulder portion

[0124] 419 bearing

[0125] 43 thrust bearing

[0126] 44 thrust member

[0127] 5 actuation device

[0128] 6 first actuation drive

[0129] 61 cam disk

[0130] 62 cam disk (integral with spindle nut 72)

[0131] 63 ball

[0132] 64 raceway

[0133] 65 gear

[0134] 66 ball cage

[0135] 67 recess

[0136] 7 second actuation drive

[0137] 71 threaded spindle

[0138] 72 spindle nut (integral with cam plate 62)

[0139] 73 drive

[0140] 74 hub component

[0141] 75 gear

[0142] 76 slot

[0143] 8 friction element

[0144] 81 friction surface

[0145] 9 counter friction element

[0146] 91 counter friction surface

[0147] 92 drive

[0148] 93 spring element

[0149] A axis

[0150] R wheel axis

[0151] V adjustment direction

[0152] L air gap

[0153] M motor shaft

Claims

1. An electromechanical brake device (1) for a motor vehicle, comprising a drive carrier (100), to which an electric motor (41, 42) and an actuating device (5) are attached, the actuating device being coupled to a motor shaft (411, 421) in a geared manner and by which a brake member (22) can be adjusted, in, The motor (41, 42) has a motor housing (413, 423), in which the motor shaft (411, 421) extending in the axial direction is mounted in a front bearing cover (414, 424) and protrudes axially from the front bearing cover (414, 424). wherein the motor housing (413, 423) is fixed to the drive carrier (100), It is characterized by: The drive carrier (100) has a recess (101) in which the motor housing (413, 423) can be received in a form-fitting and locking manner in the axial and radial directions, wherein the motor housing (413, 423) can be supported on the front side against an axial support surface (104) of the recess (101).

2. The braking device according to claim 1, characterized in that The support surface (104) is formed on a protrusion (103) which protrudes radially inward in the recess (101).

3. Braking device according to any one of the preceding claims, characterized in that The bearing cover (414, 424) is attached to the motor housing (413, 423) on the front side.

4. Braking device according to one of the preceding claims, characterized in that The bearing caps (414, 424) are axially supported against the bearing surface (104).

5. Braking device according to one of the preceding claims, characterized in that The bearing cap (414, 424) is supportable between the support surface (104) and the motor housing (413, 423).

6. Braking device according to one of the preceding claims, characterized in that The motor housing (413, 423) has a flange element (417) which is axially spaced apart from the end side and projects radially beyond the recess (101).

7. Braking device according to one of the preceding claims, characterized in that The motor housing (413) at least partially has a hollow cross section, and the bearing cover (414) can be fixed to the hollow cross section in a form-fitting manner.

8. Braking device according to one of the preceding claims, characterized in that The motor housing (413), the bearing cover (414) and / or the drive carrier (100) comprise cast parts.

9. Braking device according to one of the preceding claims, characterized in that An elastic retaining element (106) and / or a sealing element (106) is arranged between the recess (101) and the motor housing (413).

10. Braking device according to one of the preceding claims, characterized in that The driver carrier (100) has at least two recesses (101).

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